is that you in your avatar? It looks like your heels so I didn't think you were in the USPF or USAPL.
Another important thing is the collar. I use the f6 so this may not exactly translate to a katana, but for my opener I have the collar pretty high and then pull it down a little with each attempt. This allows for a fairly light opener while still getting maximum carryover with heavier weights.
I also think it would be a good idea to hit at least a 95-100% single. If I were in your position and had missed because I couldn't touch, I would put at least another 10-15 pounds on and give it another go. If you know you can bench 600, I don't see anything wrong with missing a touch at 530 and jumping to 550. If 545 is the heaviest you have ever gone though, I would be less confident in making this jump.